Analog (adjective)

1. Relating to or using signals or information represented by a continuously variable physical quantity such as spatial position, voltage, etc.
2. Similar or equivalent to something else in function or form.

Origin:

Mid 17th century: from greek analogos "proportionate, having a common ratio", from ana- "upon" + logos "ratio".

Examples:

1. The analog signal was converted to digital format.
2. Analog watches are becoming less common because of digital watches.
3. The analog circuit was replaced by a digital circuit.
4. Analog recording uses a continuous signal to record sound.
5. The analog computer was replaced by a digital computer.